“Vous voyez par là, Monsieur le Maire, que depuis 25 ans on n’a réuni, ni pu réunir aucun échantillon pour former des collections d’histoire naturelle à Toulouse, aussi il n’en existe aucune, du moins pour la partie zoologique et minéralogique, attachée à quelque établissement public.” Following a query on the existence of natural history collections issued by the mayor of Toulouse, the reply made to him by Isidore Picot de Lapeyrouse, then an assistant professor at the Faculty of Science of Toulouse and assistant director of the Jardin des Plantes was unambiguous: if it was not for a few amateurs’ cabinets, there was no such thing as a public natural history collection in Toulouse. As the son and closest collaborator to Philippe Picot de Lapeyrouse, the owner of one of the largest and renowned collection in the French Midi, the observation made by Isidore Picot de Lapeyrouse may seem unexpected. Indeed, the French revolutionary period had seen the mushrooming of many cabinets in other French provincial cities, especially following the creation of école centrales. This period is often identified as a turning point in the transfer of property of private collections into public museums. But in spite of the existence in Toulouse of a large and authoritative collection of botanical and mineralogical specimens belonging to his father, this private collection never really transformed into a public museum, even after Philippe Picot de Lapeyrouse's death. This paper tries to illuminate this failing process by looking at the successive lives of the Lapeyrouse collection.